Procedure. The 12 subjects were divided randomly into two groups (Group 1 and Group
2) of 6 each. The subjects in Group 1 were instructed to always recall by row and the
subjects in Group 2 were to recall by column when given the partial-report task. They
were tested (across nine sessions) in the order (from left to right) described in Rows 1, 2,
and 3, respectively, in Table 1. All subjects were given the whole-report task in Session 6
and the partial-report task in all other sessions. This testing sequence was adopted in
order to minimize any effect due to the order of testing.
The sequence of events involved in a trial under the whole-report condition is depicted in
the upper panel of Figure 2. Upon hearing "Ready" from the experimenter, the subject
was shown a "+" (which served as the fixation point) for 1,500 msec. After .75 sec, a
nine-letter display was shown for 50 msec. The subject was instructed to recall (as soon
as possible) as many letters as possible.
3 x 3
+ display
Figure 2. Sequence of events in the whole-report and the partial-report tasks.
The event sequence constituting a partial-report trial is depicted in the lower panel of
Figure 2. Again, "Ready" from the experimenter indicated the onset of a trial. A "+" was
first shown for 1,500 msec. After an interval of 750 msec, a nine-letter display was
shown for 50 msec. One of three equally probable tones followed the nine-letter display
at various delays. The subject was instructed to recall the top row (or the leftmost
column) if a high tone was presented, the middle row (or the central column) if a medium
tone was presented, and the bottom row (or the rightmost column) if the tone was a low
tone.